Bone Marrow is obtained from adult Acute Lymphoid Leukemia patients. Bone Marrow-Mononuclear Cells are isolated from bone marrow by diluting the whole bone marrow with phosphate buffered saline and using gradient separation techniques. Mononuclear Cells can be processed to isolate subpopulations. Acute Lymphoid Leukemia-Bone Marrow-Mononuclear Cells are available in the newly diagnosed and relapsed/refractory stages.